If Dentist Didn't Do It, Who Did?

Lawyers For The Estate Of David Acer Reject The Theory That He Infected 5 Patients With Aids. The Cdc Can't Find Any Other Explanation.

September 7, 1991|By Steve Sternberg, Atlanta Journal-Constitution

JENSEN BEACH — For 20 months, government and private investigators have been seeking clues to a crucial mystery: how patients of dentist David Acer became infected with the virus that causes AIDS.

No one yet knows. We may never know. But the case is at the center of a huge firestorm that may dictate national AIDS policies governing doctors and patients for years to come.

Acer died of AIDS last September. One of his patients, Kimberly Bergalis, went public with her story a year ago today and now, though very ill, is helping to lead a legislative fight to test certain health-care workers and patients for the human immunodeficiency virus that causes AIDS. Four other of Acer's patients have tested positive for the AIDS virus.

Of the nearly 187,000 recorded cases of AIDS in the United States, the five associated with Acer are unique: They represent the only known instances in which a health-care worker apparently infected his patients.

Or did he?

Using legal tools not available to medical investigators, lawyers defending the dentist's estate and his former employers are now trying to raise doubts about the links established by experts.

Their questions underscore the limitations of epidemiology - the science in which trained medical investigators reconstruct the past to discover the cause of epidemics.

Epidemiologists interview victims, test lab specimens and use powerful statistics to link a cause with its consequences. The Centers for Disease Control in Atlanta still has a team of experts here, working on the case.

It is medical police work, of a sort. But epidemiology cannot employ the subpoenas and court orders of the law.

All five patients have now sued Acer's estate; three of them have settled for nearly $3 million in damages.

Amid a flurry of inconsistencies in the stories of the infected patients, Dr. Harold Jaffe, head of the CDC investigation, says, ''There are certain powers we do not have. We cannot compel people to tell us the truth.''

Jaffe said the CDC cannot precisely reconstruct what happened. Instead, it has a strong ''circumstantial argument'' that Acer infected his patients.

''The laboratory work was done in a first-class laboratory, and the analysis was done by the person who is recognized as a world leader in his field,'' Jaffe said. ''That's the best we can do.''

Still, the government concedes that its investigation leaves dangling questions. For instance:

Is it possible the patients were exposed to AIDS through sexual contact, outside the dentist's office?

The first three patients identified - Bergalis, Barbara Webb and Richard Driskill - initially denied having risky sexual behavior or drug use that might have exposed them to AIDS. But as their lawyers and attorneys for Acer volley back and forth over lawsuits, those stories have been challenged:

- Bergalis, who is seriously ill with AIDS, insisted then and now that she has never had sexual intercourse. But the Acer attorneys subpoenaed her for a physical examination and tests, and last November a gynecologist concluded that Bergalis had genital warts, which studies indicate are generally caused by a sexually transmitted virus.

- Webb, originally reported to the CDC as having ''no identified risk,'' acknowledged being separated from her husband in 1981 and having an affair with a professor, said her lawyer, though the professor tested negative for AIDS.

- Driskill, listed by the CDC as having an ''unconfirmed'' risk, has acknowledged that he has had multiple female sex partners - and Acer's lawyers have subpoenaed other sexual partners who allege engaging in risky sexual behavior with him.

- Another patient, Lisa Shoemaker, 34, had lived with a man who tested positive for the HIV virus, although it isn't the same strain of the virus Shoemaker carries.

The fifth patient, John Yecs, 34, was released this month from a Florida jail.

To Acer's attorneys, the backgrounds provided by the patients - and inconsistencies in their stories - raise doubts about the claims made naming him as the source of their infection.

To the CDC, the key lies in a highly sophisticated test that found the genetic structure of the viruses in the five patients matches the strain that killed Acer. Dr. Gerald Myers at the Los Alamos National Laboratory found that the strains from Acer and his patients have a ''signature pattern'' of amino acids that have not been seen in other viruses tested in the United States.

''There is no question that Acer infected them,'' said Robert Montgomery, a lawyer for Webb.

Assuming Acer is the source of patient infection, how did it happen? Did he cut himself and infect them while doing dental work?

Acer's hygienist, Margaret Crawford, and one of his dental assistants have testified that the dentist ''always'' wore latex gloves, a mask and glasses; he also adopted more stringent infection control procedures in December 1987, before Webb and Bergalis became his patients, they said.